Pulley



Aug. 27, 1940. GUYER v 2312,77 1

' PULLEY I Filed Dec. 22, 1939 2 Sheets-$heet 1 Inventor I James age) 1@Am' A ttomey Patented Aug. 27, 1940 UNITED STATES PATENTF OFFl-(ZE, r

2 Claims. (01. 192-58) My invention relates to improvements in pulleysfor use more particularly as automobile engine equipment, for instance,in driving the fan, generator, or water pump.

As is well-known, such adjunctive mechanisms of an automobile powerplant are designed to function at maximum efliciency at a predeterminedspeed and higher speed operation thereof does not increasetheirefficiency but merely results in wear and reduces horse-power ofthe engine.

The principal object of my invention is to provide a simply constructedefficient pulley adapted under high speed operation ofv an engine todrive such adjunctive parts of an automobile power plant as those aboveindicated at a lower speed, thereby prolonging the life of such partsand providing for obtaining more power from the engine.

Another object is to provide a device of the character and for thepurpose above set forth embodying a fluid clutch reducing'friction to aminimum.

To the accomplishment of the above, and subordinate objects'presentlyappearing, a preferred embodiment of my invention has beenillustrated inthe accompanying drawings, set forth in detailin the succeedingdescription and defined in the claims appended hereto.

In said drawings:

Figure 1 is a view in transverse section taken on the line l--l ofFigure 2 looking in the direction indicated by the arrows andillustrating the preferred embodiment of my invention,

Figure 2 is a view in section taken on the line 2-2 of Figure 1 lookingin the direction indicated by the arrows, and

Figure 3 is a view in perspective of one of the paddles.

Referring to the drawings by numerals, the illustrated embodiment of myimproved pulley comprises an outer unit I and an inner unit 2,relatively rotatable. The outer unit I comprises a pair of dishedcircular sections 3, 4, each having a radial external edge web 5extending around the same and merging into an oblique flange 6. Thesections 3, 4, are secured together in concntricrelation' open sidesopposite so as to form a circular-oil containing chamber I therein. Thesecuring means comprises bolts 8 extending through the webs 5 in; suchrelation of the sections, said'webs and flanges 6 in'such relation ofthe sections forming a belt groove 9 around the unit i. A plurality ofnormally radial blade-like paddles I0 are hinged, as

at ll, to the circum ferential walls of the chamber 1 at equi-distantlyspaced points around the same and to extend uniformly into the chamber1, said paddles being of elongated rectangular form and extending 5lengthwise across the chamber I with a slight clearance between theendsthereof and the side walls of the chamber. As will be clear from aninspection of Figure 2, the axes of the hinges II are parallel with theaxis of rotation of the unit I whereby the paddles iii are swingableinto and from radial position. The sections 3, 4, are provided withtransverse ribs l2 mating in pairs end to end and formingcircumferentially spaced stops in the chamber 1 adjacent the hinges IIon one side of the paddles I0 blocking swinging of .thelatter in onedirection from radial position. A pair of coil springs l3 suitablyconnected to each paddle l0 and to the inner circumferential wall of thechamber I, at opposite .ends of the paddle, respectively, yieldinglyretain the paddles (0 in radial positions against said ribs l2 andtension the same against swinging away from the said ribs into positionstangential to the inner circumferential wall of the chamber 1.

The inner unit 2. comprises a shaft l4 extending axially into thechamber I and journalled within the chamber in a pair of bearings l5provided on the side walls of the chamber I, respectively, said bearingsincluding anti-friction assemblies IS. The shaft l4 extends out of oneunit 4 through a suitable stufling box l1 and the extending end thereofis socketed, as at i8, and provided with a set screw I9 for attachmentto a shaft, not shown. The shaft l4 has a radial web 20 in the plane ofthe unit I carrying an annular rim 2| concentric to the axis of theshaft and spaced from the inner ends of the paddles l0, said rimextending across the chamber 1 with a slight clearance for rotationtherein. A pair of diametrically opposite peripheral bosses 22 areprovided on the rim 2| having outer faces 23 concentric to the rim andof a length to span at least three of the paddles i0. respectively.Intermediate the bosses 22 radial paddles 24,- similar to paddles ID,are provided on the rim 2! to extend radially therefrom, said paddles 24being integral with said rim and spaced apart equidistantly from eachother and from the bosses 22.

Referring now to the operation, when the pulleyis used to drive anadjunctive mechanism of the automobile power plant, the shaft l4 of theinner unit 2 is fixed to the operating shaft of the mechanism to bedriven, by means of the socket i8 and set screw l9 and the outer unit I5| is suitably connected by a belt, not. shown, to the engine to bedriven thereby. The outer unit I is designed to be driven, as indicatedby the arrow in Figure 2, ins direction such that the ribs or stops i2are leading and the paddles It trail said ribs. The chamber 1 is filledwith oil. The revolution of the paddles It being opposed by resistanceof the oil, substantially r cketed between said paddles HI ,and thebosses 22 and paddles 24, a torque drive is imparted to the unit 2 bythe unit I. As the speed of operation of the v units increases-theresistance set up by the oil increases in proportion to the increase inload on shaft l4 occasioned by higher speed operation thereof. v At thispoint, .it should be explained, that the normal clearance between thepaddles III and theabutments 22 and paddles 24 is just sufilcient topermit the paddles III to pass abutments 22 and paddles 24 so thatleakage of oil through said clearance is negligible normalLv. Also thesprings l3 are constructed and arranged so that as theincreasing.resistance set up by the oil results in a predetermined degree of backpressure against paddles I0, said springs will yield permitting paddlesID to swing rearwardly, as regards the direction of rotation,and intotangential positions thereby-permitting oil to pass freely between saidpaddles l0 and abutments 22 and paddles 24 so that the torque effectbetween the .two units-is decreased with the result that the unit I ispermitted to over-run theunit 2, and unit 2 is slowed down relative tounit I. It

should also beexplained that springs II are arranged so as to overcomecentrifugal forces'tending to move the paddles lfl 'rearwardly, and soas to permit the unit I to overcome the inertia of unit 2 initially.

The abutments 22, at high-speed operation of unit I, prevent the oilfrom racing freely between the paddles I0, 24. u

Obviously the inner unit 2 may be used to drive the outer unit bysuitably attaching the same to the crank shaft of the engine. In thisuse of the pulley, the unit 2' is rotated inthe opposite direction tothat previously described to similarly rotate the unit I, the operationbeing the same except that the paddles 24 and abutments 22 become theimpelling means and the unit I is perlo ,mitted to slow downinstead ofunit 2.

The foregoing will, it is believed, suffice to impart a clearunderstanding of my invention without further explanation.

Manifestly the invention, as described, is suseeptible of modificationwithout departing from the inventive concept and rightis herein reservedto such modifications as fall within the scope of the subjoined claims.5 u what I claim is:

i. In a device orthe class described, a drumlike outer section'forming acircular oil containing chamber, -circumferential exterior flanges onfrom in circumferentially spaced relation, and

adapted to clear the inner ends of said first mentioned paddles inclosev proximity to said ends in. the radial position of said firstmentioned paddles.

2. In a device of the class described, a drum! like outer sectionforming a circular oil containing chamber, circumferential exteriorflanges on said unit providinga belt guide thereon,.an axial shaftrotatably mounted in said unit and extending out of one side thereof, anannular concentrlc rim fast on saidshaft within said chamber, aplurality of paddles in' said chamber extending transversely thereof andhinged to the inner circumferential wall thereof in circumferentiallyspaced relation for swinging movement thereon into and fromsubstantially radial positions, means yieldingly retaining said paddlesin radial position for swingingmovement therefrom in' one direction, anda plurality of transverse paddles on said rim extending radiallyoutwardly therefrom in circumferentially spaced relation and adapted toclear the inner ends of said first 45 in the radial position of saidfirst mentioned paddles, said means including stops on thecircumferential wall of said chamber establishing the radia1 position ofsaid first mentioned 5 paddles.

' mentioned paddles in .close proximity to said ends Y JAMES H. Gums.

